diff --git a/pkg/utils/subst/subst.go b/pkg/utils/subst/subst.go
index b89e7e9685..5ef68e423e 100644
--- a/pkg/utils/subst/subst.go
+++ b/pkg/utils/subst/subst.go
@@ -5,6 +5,8 @@
 package subst
 
 import (
+	"reflect"
+
 	"github.com/goccy/go-yaml"
 	"github.com/goccy/go-yaml/ast"
 	"github.com/goccy/go-yaml/parser"
@@ -121,25 +123,23 @@ func (f *fileinfo) SubstituteByValue(path string, value interface{}) error {
 		err  error
 		data []byte
 	)
-	if f.json {
-		data, err = runtime.DefaultJSONEncoding.Marshal(value)
-	} else {
-		data, err = runtime.DefaultYAMLEncoding.Marshal(value)
-	}
-	if err != nil {
-		return err
-	}
-	return f.substituteByData(path, data)
-	/*
-		node, err := yaml.ValueToNode(value)
-		if err != nil {
-			return errors.Wrapf(err, "cannot unmarshal value")
-		}
 
-		p, err := yaml.PathString("$." + path)
+	// Do not marshal the value if it's a primitive type.
+	switch reflect.ValueOf(value).Kind() {
+	case reflect.String:
+		data = []byte(value.(string))
+	case reflect.Slice:
+		data = value.([]byte)
+	default:
+		if f.json {
+			data, err = runtime.DefaultJSONEncoding.Marshal(value)
+		} else {
+			data, err = runtime.DefaultYAMLEncoding.Marshal(value)
+		}
 		if err != nil {
-			return errors.Wrapf(err, "invalid substitution path")
+			return err
 		}
-		return p.ReplaceWithNode(f.content, node)
-	*/
+	}
+
+	return f.substituteByData(path, data)
 }
diff --git a/pkg/utils/subst/subst_test.go b/pkg/utils/subst/subst_test.go
index ba9fa09c7c..f2f7db0e17 100644
--- a/pkg/utils/subst/subst_test.go
+++ b/pkg/utils/subst/subst_test.go
@@ -5,7 +5,6 @@
 package subst
 
 import (
-	"fmt"
 	"strings"
 
 	. "github.com/onsi/ginkgo/v2"
@@ -49,34 +48,33 @@ data:
 			content, err := Parse([]byte(data))
 			Expect(err).To(Succeed())
 
-			Expect(content.SubstituteByValue("data.value1", `-----BEGIN CERTIFICATE-----
-MIIDjjCCAnagAwIBAgIQAzrx5qcRqaC7KGSxHQn65TANBgkqhkiG9w0BAQsFADBh
-MQswCQYDVQQGEwJVUzEVMBMGA1UEChMMRGlnaUNlcnQgSW5jMRkwFwYDVQQLExB3
-d3cuZGlnaWNlcnQuY29tMSAwHgYDVQQDExdEaWdpQ2VydCBHbG9iYWwgUm9vdCBH
-MjAeFw0xMzA4MDExMjAwMDBaFw0zODAxMTUxMjAwMDBaMGExCzAJBgNVBAYTAlVT
-MRUwEwYDVQQKEwxEaWdpQ2VydCBJbmMxGTAXBgNVBAsTEHd3dy5kaWdpY2VydC5j
-b20xIDAeBgNVBAMTF0RpZ2lDZXJ0IEdsb2JhbCBSb290IEcyMIIBIjANBgkqhkiG
-9w0BAQEFAAOCAQ8AMIIBCgKCAQEAuzfNNNx7a8myaJCtSnX/RrohCgiN9RlUyfuI
-2/Ou8jqJkTx65qsGGmvPrC3oXgkkRLpimn7Wo6h+4FR1IAWsULecYxpsMNzaHxmx
-1x7e/dfgy5SDN67sH0NO3Xss0r0upS/kqbitOtSZpLYl6ZtrAGCSYP9PIUkY92eQ
-q2EGnI/yuum06ZIya7XzV+hdG82MHauVBJVJ8zUtluNJbd134/tJS7SsVQepj5Wz
-tCO7TG1F8PapspUwtP1MVYwnSlcUfIKdzXOS0xZKBgyMUNGPHgm+F6HmIcr9g+UQ
-vIOlCsRnKPZzFBQ9RnbDhxSJITRNrw9FDKZJobq7nMWxM4MphQIDAQABo0IwQDAP
-BgNVHRMBAf8EBTADAQH/MA4GA1UdDwEB/wQEAwIBhjAdBgNVHQ4EFgQUTiJUIBiV
-5uNu5g/6+rkS7QYXjzkwDQYJKoZIhvcNAQELBQADggEBAGBnKJRvDkhj6zHd6mcY
-1Yl9PMWLSn/pvtsrF9+wX3N3KjITOYFnQoQj8kVnNeyIv/iPsGEMNKSuIEyExtv4
-NeF22d+mQrvHRAiGfzZ0JFrabA0UWTW98kndth/Jsw1HKj2ZL7tcu7XUIOGZX1NG
-Fdtom/DzMNU+MeKNhJ7jitralj41E6Vf8PlwUHBHQRFXGU7Aj64GxJUTFy8bJZ91
-8rGOmaFvE7FBcf6IKshPECBV1/MUReXgRPTqh5Uykw7+U0b6LJ3/iyK5S9kJRaTe
-pLiaWN0bfVKfjllDiIGknibVb63dDcY3fe0Dkhvld1927jyNxF1WW6LZZm6zNTfl
-MrY=
------END CERTIFICATE-----`)).To(Succeed())
+			Expect(content.SubstituteByValue("data.value1", `|
+    -----BEGIN CERTIFICATE-----
+    MIIDjjCCAnagAwIBAgIQAzrx5qcRqaC7KGSxHQn65TANBgkqhkiG9w0BAQsFADBh
+    MQswCQYDVQQGEwJVUzEVMBMGA1UEChMMRGlnaUNlcnQgSW5jMRkwFwYDVQQLExB3
+    d3cuZGlnaWNlcnQuY29tMSAwHgYDVQQDExdEaWdpQ2VydCBHbG9iYWwgUm9vdCBH
+    MjAeFw0xMzA4MDExMjAwMDBaFw0zODAxMTUxMjAwMDBaMGExCzAJBgNVBAYTAlVT
+    MRUwEwYDVQQKEwxEaWdpQ2VydCBJbmMxGTAXBgNVBAsTEHd3dy5kaWdpY2VydC5j
+    b20xIDAeBgNVBAMTF0RpZ2lDZXJ0IEdsb2JhbCBSb290IEcyMIIBIjANBgkqhkiG
+    9w0BAQEFAAOCAQ8AMIIBCgKCAQEAuzfNNNx7a8myaJCtSnX/RrohCgiN9RlUyfuI
+    2/Ou8jqJkTx65qsGGmvPrC3oXgkkRLpimn7Wo6h+4FR1IAWsULecYxpsMNzaHxmx
+    1x7e/dfgy5SDN67sH0NO3Xss0r0upS/kqbitOtSZpLYl6ZtrAGCSYP9PIUkY92eQ
+    q2EGnI/yuum06ZIya7XzV+hdG82MHauVBJVJ8zUtluNJbd134/tJS7SsVQepj5Wz
+    tCO7TG1F8PapspUwtP1MVYwnSlcUfIKdzXOS0xZKBgyMUNGPHgm+F6HmIcr9g+UQ
+    vIOlCsRnKPZzFBQ9RnbDhxSJITRNrw9FDKZJobq7nMWxM4MphQIDAQABo0IwQDAP
+    BgNVHRMBAf8EBTADAQH/MA4GA1UdDwEB/wQEAwIBhjAdBgNVHQ4EFgQUTiJUIBiV
+    5uNu5g/6+rkS7QYXjzkwDQYJKoZIhvcNAQELBQADggEBAGBnKJRvDkhj6zHd6mcY
+    1Yl9PMWLSn/pvtsrF9+wX3N3KjITOYFnQoQj8kVnNeyIv/iPsGEMNKSuIEyExtv4
+    NeF22d+mQrvHRAiGfzZ0JFrabA0UWTW98kndth/Jsw1HKj2ZL7tcu7XUIOGZX1NG
+    Fdtom/DzMNU+MeKNhJ7jitralj41E6Vf8PlwUHBHQRFXGU7Aj64GxJUTFy8bJZ91
+    8rGOmaFvE7FBcf6IKshPECBV1/MUReXgRPTqh5Uykw7+U0b6LJ3/iyK5S9kJRaTe
+    pLiaWN0bfVKfjllDiIGknibVb63dDcY3fe0Dkhvld1927jyNxF1WW6LZZm6zNTfl
+    MrY=
+    -----END CERTIFICATE-----`)).To(Succeed())
 
 			result, err := content.Content()
 			Expect(err).To(Succeed())
 
-			fmt.Println("========= block result ===========")
-			fmt.Println(string(result))
 			expected := `
 data:
   value1: |
@@ -104,9 +102,6 @@ data:
     -----END CERTIFICATE-----
   value2: orig2
 `
-			fmt.Println("========= block expected ===========")
-			fmt.Println(expected)
-
 			Expect(strings.Trim(string(result), "\n")).To(Equal(strings.Trim(expected, "\n")))
 		})
 
@@ -124,7 +119,6 @@ data:
 			result, err := content.Content()
 			Expect(err).To(Succeed())
 
-			fmt.Printf("\n%s\n", string(result))
 			Expect(strings.Trim(string(result), "\n")).To(Equal(strings.Trim(`
 data:
   value1:
@@ -175,7 +169,6 @@ data:
 			result, err := content.Content()
 			Expect(err).To(Succeed())
 
-			fmt.Printf("\n%s\n", string(result))
 			Expect(strings.Trim(string(result), "\n")).To(Equal(strings.Trim(`
 data:
   value1:
@@ -206,7 +199,6 @@ value2: ""
 		result, err := content.Content()
 		Expect(err).To(Succeed())
 
-		fmt.Printf("\n%s\n", string(result))
 		Expect(strings.Trim(string(result), "\n")).To(Equal(strings.Trim(`
 {"data": {"value1": {"value1": "v1", "value2": ""}, "value2": "orig2"}}
 `, "\n")))
@@ -268,7 +260,6 @@ data: {
 		result, err := content.Content()
 		Expect(err).To(Succeed())
 
-		fmt.Printf("\n%s\n", string(result))
 		Expect(strings.Trim(string(result), "\n")).To(Equal(strings.Trim(`
 data:
   value1: